Restore Your Buick’s Shifting Performance
If your 2006-2007 Buick Rainier is suffering from harsh shifts, getting stuck in gear, or throwing transmission codes, the culprit is often a failing Transmission Control Module (TCM). As a technician with over two decades of experience, I’ve seen firsthand how a faulty TCM can sideline an otherwise reliable vehicle. This isn’t just an inconvenience; it’s a critical failure that affects drivability and safety. This T42 series TCM, part number 24230461, is the definitive solution, designed to restore the precise, smooth operation you expect from your vehicle.
The TCM is the electronic brain of your automatic transmission. It processes data from various sensors to control shift points, torque converter clutch engagement, and line pressure. When it fails, the communication breaks down, leading to the frustrating symptoms you’re likely experiencing. Our module is the answer. We pre-program it to your vehicle’s specific VIN, ensuring it works perfectly right out of the box. This eliminates the need for an expensive trip to the dealership for programming, saving you both time and money. This is the same reliable fix I’ve used in my own service bay for years.
A Technician’s Notebook: The Intermittent Rainier
A customer brought in their ’07 Rainier, complaining that it would randomly get stuck in 3rd gear, but only after driving for 20+ minutes. The check engine light was on, but the codes were inconsistent. After checking the wiring and solenoids, which tested fine, experience pointed to the TCM. Heat soak was causing an internal electronic failure. We installed one of our VIN-programmed modules, and the problem was solved instantly. The customer avoided a costly diagnostic rabbit hole and was back on the road the same day with a smooth-shifting SUV.
Is Your Buick Rainier Showing These Telltale Signs?
A failing Rainier Transmission Control Module can manifest in several ways. If you notice any of the following, it’s time for a diagnosis:
- ✔ Harsh, clunky, or delayed gear shifts.
- ✔ The vehicle is stuck in a single gear (often called “limp mode”).
- ✔ Check Engine Light or Transmission Warning Light is illuminated.
- ✔ Your scan tool shows DTCs like P0700 (Transmission Control System Malfunction) or various solenoid-specific codes (e.g., P0750, P0751, etc.).
- ✔ A noticeable decrease in fuel economy.
- ✔ The transmission seems to slip out of gear or fails to downshift properly.
Get Your Rainier Shifting Smoothly: A 30-Minute Install Guide
One of the best features of this module is its straightforward installation. For the 2006-2007 Buick Rainier, the process is simple enough for a confident DIYer to complete in their own driveway.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts and to help reset the system.
- Locate the TCM: On the Rainier, the TCM is typically found in the engine compartment. Check near the air cleaner box or on the driver’s side of the engine bay. It’s a silver box with electrical connectors.
- Disconnect and Remove: Carefully unplug the electrical harnesses from the old module. Press the release tabs firmly. Then, unbolt the module from its mounting bracket.
- Install the New Module: Bolt the new, pre-programmed TCM into place. Securely reconnect the electrical harnesses, ensuring they click into place.
- Final Steps: Reconnect the negative battery terminal. Start the vehicle and let it idle for a moment. While the module is plug-and-play, it’s always good practice to use a scan tool to clear any stored historical fault codes.
Confirmed Vehicle Fitment
While this is the perfect Rainier Transmission Control Module for 2006-2007 models, this T42 TCM is also compatible with a wide array of other General Motors vehicles. It is interchangeable with part numbers 24252114, 24234503, 24234274, and more. Please verify your vehicle in the list below:
Buick: Rainier (06-07), Allure (06-09), LaCrosse (06-09), Lucerne (06-11), Rendezvous (06-07)
Chevrolet: Silverado, Tahoe, Suburban, Avalanche, Express, Colorado, Impala, Monte Carlo, Cobalt, HHR, Malibu
GMC: Sierra, Yukon, Savana, Canyon, Envoy
Cadillac: DTS (06-11)
Pontiac: G5, G6, Grand Prix, Pursuit
Saturn: Aura, Ion, Vue
Hummer: H3 (08-10)
Saab: 9-7X (06-09)
Note: This is a partial list. Always verify fitment by part number or by using our vehicle selector tool.
Frequently Asked Questions
Frequently Asked Questions
What does ‘VIN Programmed’ mean for me?
It means we flash the module with your vehicle’s unique 17-digit Vehicle Identification Number (VIN) and the latest GM software before we ship it. This ensures it communicates perfectly with your vehicle’s other computers (like the ECM) right out of the box, with no extra programming required.